Dipole antenna having detachable connector at antenna-to-lead-in junction



March 26, 1963 w. L. SCHWESINGER 3,083,363

DIPOLE ANTENNA HAVING DETACHABLE CONNECTOR AT ANTENNA-TO-LEAD-IN JUNCTION Filed Jan. 27, 1958 -fil0 METERS.

lb 40 METERS. Fi I01 l a0 METERS.

I3 I60 METERS. 8

INVENTOR.

WILLIAM L. SCHWESINGER.

KWJW/IQ W MPG 1w ATTOR YS.

United States Patent O $383,363 DIPQLE ANTENNA HAVENG DETACHABLE (IGN- NECTOR AT ANTENNA-TQ-LEADJN JUNCIIQN William L. Schwesinger, Cincinnati, Ohio, assignor to Crosley Broadcasting Corporation, Cincinnati, Ohio,

a corporation of Ohio Filed Jan. 27, 1958, Ser. No. 711,212 2 Claims. ((11. 343-893) This invention relates to a system of replaceable antennae used in high frequency radio communication systems and particularly to dipole antenna arrangements useful in the amateur radio frequency bands.

As is well known, there are several operating frequencies within the band available for amateur radio communications. When an amateur operator desires to transmit a given frequency he often uses a folded dipole of required length suspended between two stationary structures, such as a building and a tree, etc., and the dipole is connected to the radio apparatus by means of a long transmission line. If the operator desires to transmit and receive at more than one frequency he will sometimes install as many dipoles and transmission lines as there are frequencies, and he will selectively connect the respective transmission lines into the communications equipment. Since the unused dipoles often cause interference, many operators will install only one antenna at a time and provide means for substituting another antenna when they desire to change frequencies. In each of these cases there is unnecessary cost in that a plurality of complete antennae, including transmission lines, are used, and in the latter case there is the additional disadvantage that much time is lost in installing and removing the apparatus each time the operator changes frequencies. This invention seeks to overcome these disadvantages by using a plurality of dipoles, each of which may be selectively plugged into a single and permanently installed transmission line.

It is an object of this invention to provide an antenna system having a plurality of dipoles of various lengths, each of which is adapted to be plugged quickly and economically into a single transmission line.

It is another object of this invention to provide a single transmission line that may be plugged into any one of a plurality of folded dipole elements which may be substituted easily and quickly, thereby providing an economical system of antennae designed for transmission and reception at various frequencies.

For a more complete understanding of the objects and nature of this invention, reference should now be made to the following description and to the accompanying drawings, in which:

FIG. 1 is a schematic representation of a preferred form of this invention;

FIG. 2 is an enlarged plan view, partly broken away, illustrating a folded dipole antenna and its associated male plug;

PEG. 3 is an enlarged plan view of the male plug and dipole, seen partly in cross section, taken along line 33 of FIG. 2;

FIG. 4 is an enlarged side elevation of the female portion of the plug and transmission line according to this invention; and

FIG. 5 is an enlarged end view of the female portion of the plug and transmission line.

Referring to the drawings, there is shown a folded dipole antenna 1 designed to operate at a wavelength of 160 meters, and a series of folded dipole antennae 1a to 12 designed to operate at from 80 tolO meters. As will be seen, each of the dipoles 1a to leis constructed so as to be released from or inserted into the antenna system with considerably more case and economy than shown in prior art arrangements of this nature.

Each of the folded dipoles may be constructed of conventional 300-ohm twin lead wire 2 which, as is best seen in FIGS. 2 and 3, consists of two uniformly spaced parallel wires 2a and 2b, the ends 2c of which are permanently spliced at the proper length for the given frequency. For a purpose hereinafter to be explained, the rubber insulation 35 of the 30O-ohm twin lead wire is provided with cutout portions 4 at each end of the dipole. In manufacture, a central portion of the wire 2b is cut away and the exposed ends are soldered or otherwise permanently connected to the conducting elements of a male plug 5.

The male plug 5 is composed of a suitable, non-corrosive insulator and, as is best seen in FIG. 3, is formed of an upper section 5a and a lower section 512, the lower section being recessed to receive an insulating supporting disc 6 for conducting pins 7. The exposed ends of the Wires are soldered or otherwise connected to the pins 7', and the upper section 5a and the lower section 5b may then be permanently secured and water-proofed by any convenient method. For connecting the dipole to a receiver or transmitter, the pins 7 are adapted to be inserted in a female plug which is permanently attached to the transmission line. Although other securing means may be used in accordance with the teachings of my invention, the pins are preferably in the form of banana-type plugs, as shown, or any other type of self-securing plug.

As best seen in FIGS. 4 and 5, the female plug may comprise a moulded insulating body in which tubular conducting members 9 are imbedded. The wires 10a and 19b of a long transmission line It may be soldered or otherwise secured to conducting tubular members 9, and the tubular members 9 are of a size designed to securely mate with the male pin members '7. In order to minimize line discontinuity, both the male plug 5 and female plug 8 are constructed so that the pin members 7 and the tubular members 9 deviate as little as possible from the physical size and spacing of the wires 10a and Nb in the transmission line 19 and the wires 2a and 2b in each of the dipole wires 2.

The entire assembly, including wire 2 and transmission line it is suspended between two stationary structures 12, such as buildings or trees, by means of the insulated hooks 13 inserted between the spliced ends 20 of the wires 2a and 2b, and between the cutout portions 4 in the insulator 3. Halyards 14 for raising and lowering the assembly are each connected at one end of one of the insulated hooks 13 and the other end is led over one of the pulleys 15 on the supporting structures 1-2. The dipoles may then be secured by wrapping the halyards 14 around convenient brackets 16.

When an operator desires to change frequencies, he may conveniently substitute any one of the dipoles la to 12 by simply lowering the dipole l, selecting a dipole of the desired length, and raising the new dipole into position. Thus, with the use of just one BOO-ohm twin lead transmission line it it is possible to connect the transmitter or receiver to any one of the folded dipoles by inserting the male plug of the antenna into the female plug of the transmission line. To do this it is necessary only to raise or lower the halyards, a procedure which can be accomplished easily and rapidly. Care must be taken that the halyards 14 are long enough to accommodate the shortest dipole.

Having thus described my invention, What I now claim is:

1. In combination with a flexible dipole antenna formed with a standardized electrical connector thereon, a structure for electrically connecting and mechanically supporting said antenna comprising: a pair of spaced, fixed, up-

right supports; an idler pulley mounted at equal heights on each of said supports; releasable hooks engaging the ends of said antenna; suspension lines fixedly connected to said hooks at one end, releasably connected to said supports at the other end, and passing over said idlers to raise said antenna to the horizontal; said antenna having any length less than the distance between said pulleys; and a transmission line having a complementary standardized releasable connector engaging the first-mentioned connector.

2. The invention as defined in claim 1 wherein said flexible dipole antenna and said transmission line comprise a length of 300-ohm twin lead wire, said dipole antenna being of a predetermined length for a desired frequency, and the ends of said twin lead wire being permanently spliced to provide loops for engaging said hooks. References Cited in the file of this patent UNITED STATES PATENTS 1,632,039 Oswald et'al June 14, 1927 1,733,609 Kuhn Oct. 29, 1929 2,514,992 'tEdelsohn w July 11, 1950 FOREIGN PATENTS 635,941 Great Britain i l Apr. 19, 1950 705,591 Great Britain Mar. 17, 1954 

1. IN COMBINATION WITH A FLEXIBLE DIPOLE ANTENNA FORMED WITH A STANDARDIZED ELECTRICAL CONNECTOR THEREON, A STRUCTURE FOR ELECTRICALLY CONNECTING AND MECHANICALLY SUPPORTING SAID ANTENNA COMPRISING: A PAIR OF SPACED, FIXED, UPRIGHT SUPPORTS; AN IDLER PULLEY MOUNTED AT EQUAL HEIGHTS ON EACH OF SAID SUPPORTS; RELEASABLE HOOKS ENGAGING THE ENDS OF SAID ANTENNA; SUSPENSION LINES FIXEDLY CONNECTED TO SAID HOOKS AT ONE END, RELEASABLY CONNECTED TO SAID SUP- 